IS : 3400 ( Part XVI ) - 1974 Indian Standard ( Reaffirmed 2012 ) METHODS OF TEST FOR VULCANIZED RUBBERS PART XVI MEASUREMENT BY THE USE OF THE OF CUT GROWTH OF RUB6ER ROSS FLEXING MACHINE ( Second Reprint JUNE 1993 ) lTDC 678.43:620.176.245 @ Copyright 1974 BUREAU OF INDIAN STANDARDS MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR NEW DELHI llOOU2 Gr2 h4ARG becember 1974 IS : 3400( Part XVI ) - 1974 Indian Standard METHODS OF TEST FOR VULCANIZED RUBBERS PART XVI MEASUREMENT BY THE USE OF THE Rubber Chairman DR D. BANERJEE Members SHRI A. T. BASAK SHRI SHRI OF CUT GROWTH OF RUBBER ROSS FLEXING MACHINE Committee, Representing Products Sectional CDC 6 Escon Consultants Pvt Ltd, Calcutta Directorate General of Supplies Delhi National Test House, Calcutta & Disposals, New ^ S. K.._BOSE . .. A. GHOSH [ Alfernate ) Alkali & Chemical Corporation of India Ltd, Calcutta SHRI D. K. CI~ATTERJEE DR S. K. RAY ( Altcnzale ) Export Inspection Council of India, Calcutta SHRI S. S. CHOPRA SHRI K. M. BIJLI (A/tern&e ) Ministry of Dcfcncc ( R & D ) SHRI S. L. GA~~DHI SHRI M. G. BHARCAVA( 4tematc ) Hindustan Steel Ltd, Ranchi SFIRIG. C. JAIN Railway Board SFIRI 0. N. KOHLI SIIRI M. KUMARAN Ministry of Defencc ( DGI ) Cosmos India Rubber Works Pvt Ltd, Bombay SHRI LALIT MOHANJAMNADAS SHRI PULIN L. KINARIWALA (AZ&mate ) Lathia Rubber Manufacturing Co Pvt Ltd, Bombay &RI S. V. LATHIA SHRI D. P. LATH!.% ( &em&? ) Madras Rubber Factory Ltd, Madras SHRI S. K. MATTHAN SHRI K. J. ABRAHAnf (Alternate ) All India Rubber Industries Association, Bombay DR K. N. MODAK SHRI K. R. SENCUPTA( Alternate ) Dunlop India Ltd, Calcutta SHRI S. MUKHERJEE SHRI P. N. S. MYER (Alternate) Rubber Board, Kottayam DR C. K. N. NAIR Bata India Ltd, Calcutta SHRI S. C. NANDY Bayer ( India ) Ltd, Bombay SHRI R. R. PANDIT Synthetics & Chemicals Ltd. Bombay SHRI M. M. PATEL Indian Oil Corporation Ltd, Bombay SHRI K. RAJ~OPAUL Directorate General of Technical Development, New DR N. V. C. RAN Delhi SHRI G. R. INAMDAR( Alternate ) ( Continued on page 2 ) @ OF Copyright INDIAN 1914 STANDARDS BUREAU This publication is protected under the Indian Copyright Act (XIV of 1957 ) and reproduction in whole or in part by any means except with written permission of the publisher shall be deemed to be an infringement of copyright under the said Act. IS : 3400 ( Part XVI ) - 1974 ( Continuedfiom page1 ) Representing Members SHRI B. ROY National Rubber Manufacturers Ltd. Calcutta SHRI AM~TABHA SEN ( Alternate ) Indian Rubber Manufacturers' Research Association, SHRt R. c. SYED Bombay SHRI S. K. CHOW (Alternate ) SWRI D. D. TALWALKAR All India Automobile & Ancillary Industries Association, Bombay SHRI*K. M. KHALADKAR ( Alternate ) SHRI D. DAS GUPTA, Director General, IS1 ( l?.r-oficio Member ) Deputy Director General SHRI SAT~SH CHANDER Deputy Director ( Chem ), BlS Methods of Testing Vulcanized Rubbers Subcommittee, CDC 6 : 9 CO?tVtflCr SHRl M. M. PATEL Synthetics & Chemicals Ltd, Bombay Members SHRI N. M. REOE (Altemate to Shri M. M. Pate1 ) National Test House, Calcutta SHRt S. K. BOSE SHRI A. GHOSH ( Alternab ) Bayer ( India ) Ltd, Bombay Dx S. N. CHAKRAVAR~ DR S. K. BHATNACAR(Alternate ) Alkali & Chemical Corporation of India Ltd, Calcutta SHRI D. K. CHATTERJEE SHRI K. R. SESHADRI ( A&emote ) Cosmos India Rubber Works Pvt Ltd, Bombay SHRI B. H. DALAL SHRI PULINL. KINARI~ALA ( Alternate ) Dunlop India Ltd, Calcutta SHRI S. B. GANCULY SHRI A. MUKHERJEE ( AItcrnate) Madras Rubber Factory Ltd, Madras SHR~ A. GEORGE JOHN SHRI G. R. SANRARANARAYANAN ( Alternate ) Ministry of Defence ( DGI ) SHRX R. K. GUPTA Indian Rubber Regenerating Co Ltd, Bombay SHRXG. R. KA~~SH~AR SWRI A. R. KANTAK ( AIfnnatc ) Rail@ay Board DR S. P. MANIK SHRI G. DORAI~W~Y ( Altemate ) Rubber Board, Kottayam DR C. K. N. NAIR Swastik Rubber Products Ltd, Poona SHRI V. D. PANDSE SHRI S. V. TATHAWADRAR ( Ahnate ) Sundaram Industries Pvt Ltd, Madurai SHRI V. R. RAO SHRI K. C. MADHUSUDHANAN (Alternate ) National Rubber Manufacturers Ltd, Calcutta SHRI B. ROY SHRI J. CHATIZRJEE (Ahmate) Bata India Ltd, Calcutta SHRX S. SARKAR SHRI S. ROY (A&mate ) Escon Consultants Pvt Ltd, Calcutta SHRI A. K. SEN CHAUDHURI Hindustan Latex Ltd, Trivandrum DR N. H. SIVARAMAKRISHNAN Premier Rubber & Cable Industries, Bombay SHRI M. SALtMVOHRA SHRI A. D'COSTA ( Al&mate ) 2 XVI ) -1974 M: 34W ( Pskl't Indian Standard METHODS OF TEST FOR VULCANIZED RUBBERS PART XVI MEASUREMENT' OF CUT GROWTH OF RUBBER BY THE USE OF THE ROSS FLEXING MACHINE 0. FOR E.,WORD 0.1 This Indian Standard ( Part Xvl ) was adopted by he Indian Standards @stitution on 5 April 1974, after the draft finalized by the Rubber Products Sectional Committee had been approwxl by the Chemical Division council. 0.2 In the preparation of this standard considerabk assistance has been derived from ASTM DesignationD 1052-55 ( Re-approved 1970 ) ` Standard method of test for measurement of cut growth of rubkr by the use of the Ross flexing machine' issued by the .knerican Society for Testing and Materials. `0.3 In reporting the rcsuks of a test or analysis made in accordance with this standard, if the final value, observed or czdctdatcd, is to be rounded oR', it shall be done in accordance with IS: 2-1960*. 1 q SCOPE 1.1 This stiMLdid ( Part Xlll ) Prescrib= the mc~hd for determhing the resistance of rubbe~ to cut g&th when subjected to repeated f?"~ing or bending under specific conditiom and foz known periods on Ross flexing machine. Z. APPARATWS machine is shown in Fig. 1. `I'he machine allows the"pierced fkxed area of the MSt specimen to bend freely over a rod of 10 mm diameter through an Ulgk of 90". The machine s~al~run at ~0~ + 5 cycks per minute. One ml of the test specimen is c~a~pcd fiITII~y. ~0 a h~~dm arm and the other end Is pked betwen two rolkrs ~vhich p=m~t a free bending moveficnt of the cst specimen during each cycle. *Ruies for roundbg 2.1 ROSS Fleximg ~f~wne -- .4 schematic diagram of Rcks fkxing o~ munericd vahses ( w&d). 3 A = Test specimen B = Holder arm C = Holder arm adjustment D = Adjustment roller E = Fixed lower roller F - Supporting fixed roller C = Pierced section H = Rod over which specimen bends freely through a 90" angle FIG. 1 SCHEMATIC DIAGRAM OF Ross FLEXING MACHINE 2.2 Piercing Tool and Holder - The piercing tool and holder is shown in Fig. 2. The piercing tool shall have a cutting edge 2:50 f 0.02 mm in The length of the bevel from the cutting edge along the axis of diameter. the rod shall be 6.30 f 0.40 mm. The diameter of the holes in guide block shall be, respectively, not more than 0.20 mm larger than the diameter of the piercing tool, and not more than 0.20 mm larger than the diameter of the guide rods. 2.3 Rule - A rule of suitable length, graduated in steps of 0.25 be used for measuring the length of the cut growth. 3. TEST 3.1 SPECIMEN of each sample shah be tested simultaneousIy. mm shall At least two specimens 1.0 mm in width, a 3.2 Dimensions - Each specimen shall be 25.0 f minimum of 150 mm in length and 6.30 f 0.2 mm in thickness and shall be cut, from cured slab 6-30 f 0.2 mm in thickness, of suitable dimensions. Unless otherwise specified, they shall be prepared SO that the longitudinal dimension is parallel with the direction of the grain. NOTE-When evaluating specimen of high hardness, thickness other than standard may be used as agreed between the purchaser and the supplier. 4 ISr3499(PartXVI)-1974 4. PROCEDURE 4.1 Storage of Samples and Conditioning of Test Specimen 4.1.1 The properties of vulcanized rubbers change continuously with time, these changes being particularly rapid during first 24 hours after vulcanization. Therefore, no test shall be carried out within this period. For accurate comparison between different rubbers it may be necessary to ensure that these are tested at substantially the same interval after vulcanization. 4.1.2 Samples and test specimen shall be protected from light as completely as possible during the interval between vulcanization and testing. The specimen shall be kept at a temperature 27 f 2°C for a period of not less than 3 hours immediately prior to being measured and tested. recommended temperature for test is 4.2 Temperature of Test -The 27 f 2%. Any other temperature used, shall be reported in the test report. 4.3 Method 4.3.1 The test specimen shall be pierced by the use of piercing tool. The piercing tool shall be adjusted in the holder with the cutting edge projecting 7.2 & 0.2 mm from the base of the holder so that it will pierce completely through the test specimens when tapped. Before piercing the test specimen, the test specimen shall be lubricated with a solution of soap that will The cut made by the piercing tool not react with the rubber compound. shall be parallel to the width of test specimen, at right angle to and across the longitudinal centre lines of the specimen at a point 62.0 f I.0 mm from the clamped end. 4.3.2 Clamp the test specimens to the holder arm of the flexing machine in such a .position that when the specimens are flexed at 90" the cuts are at the centre point of the arc of flexure. The holder arm shall be in a The adjustable horizontal position when the test specimens are attached. top rollers shall be let down until they just touch the test specimen and shall be locked in this position by means of the wing nuts, permitting free travel of the test specimen between the rollers during the bending movement. 4.3.3 Once the test specimen has been attached as described, the machine shall be started and run at a rate of 100 f 5 cycles per minute. The number of cycles shall be recorded by the use of counter. Frequent observations shall be made, recording the number of cycles and the increase in cut length for the purpose of determining the rate of increase in cut length. Number of cycles for the initiation of the crack from the pierced hole shall also be recokded. When observing cut growth, the holder arm shall be at an angle approximately 45" from the vertical. The test shall be continued until cut growth,has increased to specified length. 6 IS:34oO(PartXVI)-1914 4.3.4 In some cases the cut growth is not in a straight line as continuation of the cut made by the. piercing tool and ` star shaped ' crack may develop. In this event, the cut growth shall be measured as the length When it is of the longest continuous crack, regardless of its directions. necessary to stop operation of the machine, the holder arm shall be. in a horizontal position, so that the test specimens remain horizontal while not being flexed. 4.4 Report - The results from observation of at least two test specimens shall be averaged and reported as: a) the number of cycles for the initiation of crack, and b) the number of cycles for each 100 percent increase in cut growth up to and including 600 percent. BUREAU Heedquerters : OF INDIAN STANDARDS `/ Manak Bhavan, 9 Bahadur Shah Zafar Marg. NEW DELHI 110002 Telephones : 331 01 31 Telegrams : Manaksanstha 331 13 75 (Common to all Offices) Regionet Offices : Telephone Central : Manak Bhavan, 9, Bahadur Shah Zafar Marg NEW DELHI llODO2 * Eastern . 1114 C.I.T. Scheme VII M. * V.I.P. Road, Maniktola, CALCUTTA 700054 Northern : SC0 445-446, Sector 35-C, CHANDIGARH 160036 Southern : C.I.T. Campus, IV Cross Road, MADRAS 600113 t Western : Manakalava, E9 MIDC. Marol. Andheri (East), BOMBAYb00093 bench Offices : 331 01 31 ! 331 13 75 37 86 62 21843 41 29 18 6 32 92 95 t Peenya Industrial Area, 1 st Stage, Bangalore-Tumkur Pushpak', Nurmohamed Shaikh Marg. Khanpur, AHMADABAD Road, BANGALORE 560058 Gangotri Complex, 5th Floor, Bhadbhada Road, T.T. Nagar, BHOPAL 462003 380001 2 63 48 39 49 58 65 40 21 5 36 27 2 67 05 8-71 19 96 . 3 31 77 231083 6 34 71 21 68 76 5 55 07 6 23 05 6 21 04 Plot No. 82/83. Lewis Road. BHUBANESHWAR 751002 Kalai Kathir `Building, 6/48-A Avanasi Road, COIMBATORE 641037 Qualitv Markina Centre, N.H. IV. N.I,T.. FARIDABAD 121001 Savitri' Complex. 116 G.. T. Road, GHAZIABAD 201001 5315 Ward No. 29, R.G. Barua Road. 5th By-lane, GUWAHATI 781003 68-56C L. N. Gupta-Marg, ( Nampally Station Road ) HYDERABAD 500001 R14 Yudhister Marg. C Scheme, JAIPUR 302005 117/418 B Sarvodaya Nagar. KANPUR 208005 Plot No. A-9, House No. 561/63. LUCKNOW 226005 Patliputra zndustrial Estate, PATNA District Industries Centre Complex, SRINAGAR 190011 Sindhu Nagar, Kanpur Roao. 800013 Bagh-e-Ali Maidan. T. C. No. 14/1421, University P. 0.. Palayam, THIRUVANANTHAPURAM 695034 inspection Offices (With Sale Point) : Pushpanjali. First Floor, 205-A West High Court Road. Shankar Nagar Square, NAGPUR 440010 Institution of Engineers (India) Building, 1332 Shivaji Nagar. PUNE 4+1005 `Safes Office Calcutta is at 5 Chowringhee Approach, P. 0. Princep Street, CALCUTTA Sales Office is at Novelty Chambers, Grant Road, BOMBAY is at Unity Building, Narasimharaja Square, $A~~;L~~~e 52 51 71 5 24 36 27 68 00 89 65 28 22 39 71 .' `I: t Reprography Unit, BIS. New Delhi, India